Recent reports that flavorings such as chocolate and strawberry are being used to disguise the bitter taste of methamphetamine sold to children in Thailand have caused outrage, but the trend is sadly nothing new. Dealers have been actively targeting youngsters for “many years” according to narcotics experts, and the phenomenon has been recorded by law-enforcement agencies including the DEA.

However, there is now a trend of “direct enticement of kids by dealers outside schools as school finishes in the late afternoons,” says Professor Desmond Ball, an Asia specialist at the Australian National University. And with record narcotics seizures slated in Thailand for this year, the fear is that the country’s drug problem is worsening and that dealers are venturing into previously untapped markets.

Yaba is a motley form of methamphetamine that has caffeine added. The drug — aptly named “crazy drug” in Thai or “crystal” or “ice” in the West — accounts for three-quarters of all addicts seeking treatment at rehabilitation centers in Thailand. Tablets cost around $6, and the drug is popular right across the social spectrum, from laborers and sex workers striving to work longer hours, to the destitute and moneyed teenagers. A 41-year-old Buddhist monk was arrested in May after he was found to be taking the drug in his monastery in an effort to control his appetite. Pills can be swallowed, ground down and snorted or injected.

Parents were warned again this week to be on their guard after varieties of yaba that had apparently been doctored to appeal to schoolkids were seized in Bangkok. “We found that yaba makers are trying to change their product to meet the demands of targeted groups,” Dr. Viroj Verachai, director of the Princess Mother National Institute on Drug Abuse Treatment, told the Bangkok-based Nation newspaper. “These flavors help the users take the drug more easily, but it could severely affect their nervous systems.”

Typical symptoms of prolonged yaba use include psychotic episodes, hallucinations, violence, irritability, aggression, lack of concentration, sleep disturbance and short-term memory problems that affect the ability to learn, says Mike Miller, a counselor at the Cabin rehab clinic in Chiang Mai, northern Thailand. “I would imagine with brain formation not being complete for a child there would possibly different longer-term consequences,” he tells TIME, adding that it was “abhorrent” that dealers would “put profit before the future of children.” Even more worryingly, he says, “the treatment options for children are quite limited compared to adults.”

The vast majority of yaba originates from clandestine laboratories across Thailand’s western border, in rebel-held mountainous territory in Burma (officially known as Myanmar), where it is an $8 billion industry. In 2011, Thailand reported the world’s fourth highest seizures for methamphetamine — behind only Mexico, the U.S. and China — with 31 tons confiscated, according to the U.N. Office on Drugs and Crime. An estimated 30 million yaba users can be found across Southeast Asia, and methamphetamine has now replaced more traditional opium-based narcotics as the region’s principal drug of choice. The associated addiction is considered particularly fierce, and withdrawal symptoms have been linked to a variety of violent behaviors including murders, kidnappings, rapes and assaults.